Power loss and lumpy running.

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krisboats

Active Member
Posts
254
Hi guys,

Still having problems with my lumpy idle and i'm also noticing a problem with the engine suffering a loss of power.

To better describe, idling from cold the engine seems a to judder occasionally that can be felt inside the car. No problems while revving the engine and as it gets up to temperature the idle slowly drops accordingly to right around the 900rpm mark.

While driving around slowly in second the car sometimes seems to pulse or surge, as if i were moving my foot up and down slightly on the throttle. On the motorway or dual carriageway when getting up to speed the car can sometimes feel starved of power, like it takes way too long to get up to 70mph and foot to the floor throughout the gear range still has VERY gradual acceleration. Driving up to 4000rpm between shifts seems to make it seem more lively but i used to change gears ataround 3000rpm 6 months ago. Once at 70mph if i lay off the throttle it seems nice and steady but if i were to try and drop to 65 then go back up to 70mph foot to the floor wouldn't get it there.

After getting frustrated with it on the way home yesterday i tried stomping on the peddle a few times at around 65mph and after a couple of presses (and thoroughly bouncing the girlfriend around) the car came to life and raced up to the 80mph mark with little to no problem at all. After 600yards it was the same, starved of power and needed the peddle cycling to get the acceleration back.

Now i've had a google and some people said it could be the spark plugs. So with the engine running i removed the HT leads from the spakr plugs one by one, but they all made an impact to the engine sound when removed so it looks like they're probably working okay.

I've just now seen a couple of threads on here from a few years back and the guy replaced his lambda sensor which cured the jerky driving and power issues. Would it be a good course of action to jump straight into replacing the lambda sensor with one of these and see if it fixes it or is there a way to test the current one first before shelling out £50 on a tiny little sensor? Also, neither state whether they replaced the front or rear lambda or even both, as far as i understand the freebie has 2...

Any help muchly appreciated and i apologise if this seems like a stupid question. I didn't know which piece of forum etiquette to break, ask a simple question or bump a 4 year old thread.
 
Do an idle drop test on the fuel injectors, and try some injector cleaner.

Get someone with a scan tool to check for codes, and monitor the lambda sensors, particularly sensor 1.

Get the fuel pressure tested, and consider replacing the fuel filter.
 
Just because the spark plugs are all firing doesn't mean they have a strong spark. With no load a weak spark might only make a small difference but under load you'll feel it. Unless replaced recently change your plugs. If that doesn't work change leads and if that doesn't work then change coil pack(s).
Having similar but not as bad issues and just received new coil packs in the post so will report back.
On my daughters Fiesta I chased a similar fault for weeks before finding a faulty spark plug lead. It had already been replaced before replacing the coil pack but failed due to being pulled off a couple of times.

Edit Also getting some injector cleaner.
 
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Do an idle drop test on the fuel injectors, and try some injector cleaner.

Get someone with a scan tool to check for codes, and monitor the lambda sensors, particularly sensor 1.

Get the fuel pressure tested, and consider replacing the fuel filter.

Thanks mate, one quick question though...

How do i do the idle drop test? Googling throws me to a load of stuff about motorbike idles. I take it i need to disconnect them with the engine running to see if the idle gets slower, but where do i disconnect them?

The latter two would be a garage jobby then from the sounds of it. Don't know anyone with a freelander let alone someone with the tools for it.
 
Just because the spark plugs are all firing doesn't mean they have a strong spark. With no load a weak spark might only make a small difference but under load you'll feel it. Unless replaced recently change your plugs. If that doesn't work change leads and if that doesn't work then change coil pack(s).
Having similar but not as bad issues and just received new coil packs in the post so will report back.
On my daughters Fiesta I chased a similar fault for weeks before finding a faulty spark plug lead. It had already been replaced before replacing the coil pack but failed due to being pulled off a couple of times.

Edit Also getting some injector cleaner.

NGK platinum plugs, pre/self-gapped to 1.1mm? No idea on good quality HT leads, although i've a feeling plugs and leads were all changed roughly a year ago anyway. Will double check tonight on their age.
 
What year is it? Does it have a distributor cap and if so have you replaced it and the rotor arm?

It's the 98 petrol. It does have the cap and rotor arm type, although i've never taken it off before.

EDIT: Forgot to mention in the first post that the MPG is lower than it was when i first got it. £15 would get me about 70 miles, now i'm lucky if it gets me 60.
 
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rotor arm looked okay, but 2 of the prongs on the cap had a sort of powdery white build up on them. Is that why i was only being zapped by two of the ht leads when i removed them earlier?
 
Yeah, parkers parts place has them in stock down the road from me so going to pick up a new one tomorrow. cleaned the current one off a bit and sanded the contacts clean. The car is still running lumpy, but when it isn't it feels a lot smoother and like its a little more responsive.
 
Dizzy cap and rotor arm are both changed, new leads and replaced each spark plug with a fresh one.... made no difference.

Been reading up that a head gasket failure can cook an 02 sensor. Well not cook exactly, but the coolant etc getting on them during failure turns them ****. Seeing as mine died in january and it's been running like a bag of **** since then i've got one on order and will hopefully be fitting it one day this week.
 
I would pull the injectors out and give them a blast with carb cleaner. Clean the baskets facing downwards to get as much debris out of them as possible. Give the fuel rail a blast as well.

Put a tiny bit of clean oil on the rubbers when replacing them.

Not as good as ultrasonic cleaning and new injector components, but will without doubt make a difference. It's an easy job to do as well, not to mention quite rewarding.

A really duff O2 sensor even something as old as yours should still throw some lights on the dash. But without doubt its worth replacing.

Hope your cat hasn't been "Washed Out" as well. Another problem HGF and erratic running can cause.
 
I would pull the injectors out and give them a blast with carb cleaner. Clean the baskets facing downwards to get as much debris out of them as possible. Give the fuel rail a blast as well.

Put a tiny bit of clean oil on the rubbers when replacing them.

Not as good as ultrasonic cleaning and new injector components, but will without doubt make a difference. It's an easy job to do as well, not to mention quite rewarding.

A really duff O2 sensor even something as old as yours should still throw some lights on the dash. But without doubt its worth replacing.

Hope your cat hasn't been "Washed Out" as well. Another problem HGF and erratic running can cause.

Cheers for that, no idea what i'm doing with the injectors or how to remove them so will have to ask someone more knowledgable than i am tomorrow afternoon.

Before i replaced it i unplugged the old 02 sensor entirely and the car seemed to run exactly the same so i picked up a replacement NTK o2 sensor off ebay. Fitted the sensor and the car feels like it has a rocket up its exhaust pipe now! Nice and quick to accelerate in gears 1-4 again and while not much acceleration at cruising speeds it is constant and seems fairly effortless driving along and up hills again at 70.

So would i see a big improvement in cleaning the injectors as well? I did google it and watched a bunch of videos with people hooking them up to batteries and spray fluid through them to blast them out. Is that what's required for the freebie as well?
 
Cheers for that, no idea what i'm doing with the injectors or how to remove them so will have to ask someone more knowledgable than i am tomorrow afternoon.

Before i replaced it i unplugged the old 02 sensor entirely and the car seemed to run exactly the same so i picked up a replacement NTK o2 sensor off ebay. Fitted the sensor and the car feels like it has a rocket up its exhaust pipe now! Nice and quick to accelerate in gears 1-4 again and while not much acceleration at cruising speeds it is constant and seems fairly effortless driving along and up hills again at 70.

So would i see a big improvement in cleaning the injectors as well? I did google it and watched a bunch of videos with people hooking them up to batteries and spray fluid through them to blast them out. Is that what's required for the freebie as well?

Glad you got a result.

Cleaning the injectors may give you a smoother tick over and smoother engine running all round. But if its going ok then i wouldn't bother unless you fancy having a go at taking them out. As mentioned, even a basic clean with carb cleaner makes a difference.

Pro cleaning is best with ultrasonics etc. Hippos fuel injectors are included, as they are not much different from any other petrol injector.

Maybe just throw a bottle of Fortis injector cleaner in for now if your not sure on doing it yourself.
 
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